Heart valve annuloplasty prosthesis sewing cuffs and methods of making same

ABSTRACT

An annuloplasty prosthesis for a heart valve has a sewing cuff added to the conventional structure. The sewing cuff is preferably an extension of the fabric cover that is provided around the core of the prosthesis. The sewing cuff preferably extends radially outwardly from cross sections of the remainder of the prosthesis. Methods of making such a sewing cuff are also disclosed.

This application claims the benefit of U.S. provisional patentapplication No. 60/571,437, filed May 14, 2004, which is herebyincorporated by reference herein in its entirety.

BACKGROUND OF THE INVENTION

Annuloplasty prostheses for heart valves are well known as is shown, forexample, by Alfieri et al. U.S. patent application publication US2002/0173844 Al and Bolling et al. U.S. patent application publicationUS 2003/0093148 Al. Such prostheses may be complete rings (e.g., as inthe above-mentioned Alfieri et al. and Bolling et al. references), orthey may be less than complete rings (e.g., as in Carpentier U.S. patent3,656,185). The term “annuloplasty” is used herein to refer to both ofthese types of prostheses (i.e., both complete rings and less thancompletely annular structures (e.g., generally C-shaped structures)).

Typical annuloplasty prostheses include a core member surrounded by asoft fabric cover. The core member is often substantially rigid or atleast semi-rigid and not penetrable by a suture needle and suturematerial. The fabric cover may be designed to cushion the prosthesis,and possibly also to promote tissue in-growth into the prosthesis tohelp integrate the prosthesis into the patient's body. It is oftendesired to secure the prosthesis in the patient by passing one or moresuture needles and suture material through the fabric cover and adjacenttissue. Tightness and/or thinness of the fabric cover may make thisdifficult to do. Even if the surgeon is successful in getting properengagement, the amount of fabric caught may be less than would bedesirable for good tissue healing and over-growth.

SUMMARY OF THE INVENTION

To facilitate suturing an annuloplasty prosthesis into a patient, asewing cuff is added to the prosthesis in accordance with the invention.Such a sewing cuff is preferably an extension of the fabric cover thatis provided around the core of the prosthesis. The sewing cuffpreferably extends radially outwardly from cross sections of the coreand the remainder of the fabric cover. Stitching may be used tostabilize the extension. The extension may be one-piece with the fabriccover. For example, a medial portion of the cover fabric may be used toform the extension. As another example, a free edge portion of thefabric used for the cover may be used to provide the extension. The freeedge portion may be folded to increase the bulk of the extension. Twofree edge portions of the fabric used for the cover may be used togetherto form the extension. Again, folding may be used to increase the bulkof the extension.

The invention also includes various methods of making sewing cuffs suchas those summarized in the preceding paragraph.

Further features of the invention, its nature and various advantages,will be more apparent from the accompanying drawings and the followingdetailed description of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a simplified cross sectional view of an illustrativeembodiment of an annuloplasty prosthesis for a heart valve in accordancewith the invention. FIG. 1 may be taken as shown at 1-1 in FIG. 7.

FIG. 2 a is a simplified cross sectional view of an illustrativeembodiment of a component that can be used in making a prosthesis likethat shown in FIG. 1 in accordance with the invention.

FIG. 2 b is similar to FIG. 2 a, but shows a later stage in handling thecomponent in accordance with the invention.

FIG. 2 c is again similar to FIGS. 2 a and 2 b, but shows a still laterstage in accordance with the invention.

FIG. 2 d is generally similar to FIG. 1, but shows an end result fromthe progression of FIGS. 2 a-2 c in accordance with the invention.

FIGS. 3 a-3 c are each generally similar to FIG. 1, but show aprogression in an alternative approach to making a prosthesis inaccordance with the invention.

FIG. 4 is again generally similar to FIG. 1, but shows an alternativeconstruction of a prosthesis in accordance with the invention.

FIG. 5 is once again generally similar to FIG. 1, but shows anotheralternative construction of a prosthesis in accordance with theinvention.

FIG. 6 is again generally similar to FIG. 1, but shows still anotheralternative construction of a prosthesis in accordance with theinvention.

FIG. 7 is a simplified plan view of an illustrative embodiment of aprosthesis in accordance with the invention.

DETAILED DESCRIPTION

The annuloplasty prosthesis 10 cross section shown in FIG. 1 includescore member 20, a layer 30 of an elastomeric material surrounding core20, and fabric cover 40 surrounding elements 20 and 30. FIG. 1 alsoshows what may be described as a mini-sewing-cuff 50 extending radiallyoutwardly from the other elements at one angular location or regionaround the circumference of the cross section. For completeness FIG. 7shows a plan view of an entire illustrative annuloplasty prosthesis 10in accordance with the invention and which can have a cross section asshown in FIG. 1 (or as in other FIGS. subsequent to FIG. 1). AlthoughFIG. 7 shows the cross section taken at one particular location,substantially the same cross section may be found at other (or even all)locations annularly around prosthesis 10. Also, although FIG. 7 shows aprosthesis 10 that is a complete, unbroken, generally D-shaped annulus,prosthesis 10 could have other shapes, and could alternatively be only aportion of an annulus (e.g., it could be C-shaped rather than D-shaped).Still another point to be made is that although FIG. 7 shows sewing cuff50 extending around the outside of prosthesis 10, sewing cuff 50 couldalternatively be at any other location around cross sections of theprosthesis.

FIG. 7 is provided to make the point that, although most of the otherFIGS. herein are of cross sections, these other FIGS. are representativecross sections of structures that extend longitudinally (e.g., out ofthe plane of the paper on which the cross sections are drawn).

Typical materials for the various components of prosthesis 10 will bementioned later in this specification. For the moment it will besufficient to point out that elastomeric layer 30 is optional and may beomitted in some embodiments of the invention. Fabric cover 40 would thenbe directly over core 20. The FIGS. subsequent to FIG. 1 showgeneralized cores 20, which can be either like core 20 in FIG. 1 or acomposite of elements such as 20 and 30 in FIG. 1.

Sewing cuff 50 can be formed on prosthesis 10 in any of a number ofdifferent ways. Some examples are shown in subsequent FIGS. anddescribed below.

In the illustrative embodiment shown in FIGS. 2 a-2 d, a medial (or moregenerally an interior) portion of fabric 40 is gradually pinchedtogether as shown progressively in FIGS. 2 a-2 c until two interiorcreases 42 a and 42 b are formed and brought together (FIG. 2 c). A finesuture 60 is then used to sew the two creases 42 together to createsewing cuff 50. After the sewing cuff has been sewn together, the twofree ends (edges) 44 a and 44 b of fabric 40 are wrapped aroundprosthesis core 20 and stitched together as shown at 70 in FIG. 2 d.Fabric 40 is pulled tightly together during stitching 70 so that it willsecurely and firmly wrap around prosthesis core 20.

In the alternative embodiment illustrated by FIGS. 3 a-3 c, fabric cover40 is first wrapped loosely around prosthesis core 20. A portion of thefabric annulus is gradually squeezed or pinched together as shown at 41in FIG. 3 b. This eventually produces a sewing cuff. Depending on thewidth of the cuff required, the amount of fabric 40 squeezed or pinchedtogether to create the cuff can vary. Suture 60 is added to hold sewingcuff 50 together as shown in FIG. 3 c to complete the process.

In the further alternative embodiment shown in FIG. 4, sewing cuff 50 iscreated by squeezing together two otherwise free edges 46 a and 46 b offabric 40 after the fabric has been wrapped around prosthesis core 20. Afine suture 60 can then be used to stitch the two single-layers fabricedges together (and around core 20) to form the sewing cuff. The width(radial outward projection) of the cuff (dimension W in FIG. 1) can bedetermined by adjusting the amount of excess fabric 40 used to wraparound the core. More than just the single stitch line 60 can be used tohold edges 46 a and 46 b together in sewing cuff 50.

In the still further alternative embodiment shown in FIG. 5, fabric 40is loosely wrapped around prosthesis core 20 with both edges 48 a and 48b free. Free edges 48 are then folded over on themselves so that eachfree edge becomes double-layered. The two double-layered free edges arethen squeezed together, and a fine suture 60 is used to stitch thefabric together to form sewing cuff 50. A sewing cuff created in thisway can be thicker (bulkier) and provide more cushioning. Free edges 48can also be folded over multiple times to create a triple- or othermultiple-layered cuff 50.

In the further illustrative embodiment shown in FIG. 6, sewing cuff 50is first formed by folding a free edge portion of fabric 40 severaltimes as shown at 49 to get the thickness desired. This is then stitchedtogether with suture 60 so that the sewing cuff is stabilized andremains intact with the desired shape. The remaining free edge of fabric40 is used to wrap around prosthesis core 20 and then stitched to thesewing cuff as shown at 70. Fabric 40 will wrap around ring core 20securely and firmly when the process is completed.

Sewing cuff 50 may measure from about 0.25 mm to about 5.0 mm in width(see dimension W in FIG. 1 or the comparable unreferenced dimension inany of the other FIGS.). The sewing cuff may be created from a softfabric such as polyester, PTFE, or the like, and may be the same as (oreven one piece with) fabric cover 40. Sewing cuff 50 allows the surgeonto place sutures easily, and also provides substantially more fabric fortissue in-growth purposes. More sewing fabric also allows for a bettercushion between the heart valve annulus and the prosthesis. As has beensaid, sewing cuff 50 can also be used with a prosthesis core that isfirst covered by a soft elastomer 30, such as silicone or the like,before it is covered by a fabric 40 with cuff 50. The sewing cuff canalso be used on just prosthesis core 20 itself without any intermediateelastomer covering 30. Prosthesis core 20 can be made from any suitablematerial, such as stainless steel, titanium, ceramic, elgiloy,shape-memory alloy, and/or polymeric material.

It will be understood that the foregoing is only illustrative of theprinciples of the invention, and that various modifications can be madeby those skilled in the art without departing from the scope and spiritof the invention. For example, although the FIGS. herein show prostheseshaving cores 20 that are round in cross section, it will be appreciatedthat other core cross sectional shapes can be used instead if desired.

1. An annuloplasty prosthesis for a heart valve comprising: a core member; a fabric cover around the core member; and an extension of the fabric cover that extends radially outwardly from cross sections of the core member and the fabric cover for use as a sewing cuff.
 2. The prosthesis defined in claim 1 wherein the extension is substantially one-piece with the fabric cover.
 3. The prosthesis defined in claim 1 further comprising: stitching for stabilizing the extension.
 4. The prosthesis defined in claim 3 wherein the stitching is disposed between the fabric cover and the extension.
 5. The prosthesis defined in claim 4 further comprising: additional stitching for closing the fabric cover around the core member, the additional stitching being annularly spaced from the extension around the core member.
 6. The prosthesis defined in claim 1 wherein the extension is formed from at least one free edge portion of the fabric used for the fabric cover.
 7. The prosthesis defined in claim 6 wherein the at least one free edge portion is folded to increase bulk of the extension.
 8. The prosthesis defined in claim 6 wherein the extension is formed from two free edge portions of the fabric used for the fabric cover, the free edge portions being joined together in the extension.
 9. The prosthesis defined in claim 8 wherein the two free edge portions are folded in the extension.
 10. A method of making an annuloplasty prosthesis for a heart valve comprising: adding to a core of the prosthesis a sewing cuff that extends radially outwardly from a portion of a periphery of a cross section of other structure of the prosthesis.
 11. The method defined in claim 10 wherein the prosthesis includes a fabric cover surrounding the core, and wherein the adding comprises: using cover fabric to provide the sewing cuff.
 12. The method defined in claim 11 wherein the using comprises: employing a medial portion of the cover fabric to provide the sewing cuff.
 13. The method defined in claim 12 wherein the employing comprises: pinching the medial portion of the cover fabric.
 14. The method defined in claim 13 wherein the employing further comprises: stitching together cover fabric that has been pinched in the pinching.
 15. The method defined in claim 11 wherein the using comprises: employing a free edge portion of the cover fabric to provide the sewing cuff.
 16. The method defined in claim 15 wherein the employing comprises: folding the free edge portion of the cover fabric.
 17. The method defined in claim 16 wherein the employing further comprises: stitching together cover fabric that has been folded in the folding. 